It is False , because they could be in a common plane but they do not form a single line
1. A. parallel, because when you get y by itself it is y=-2x+7, the two equations have the same slope which means they are parallel.
2. B. sometimes, in order for two lines to be parallel they have to have the same slope so, it is possible that two lines say with a slope of 3, those would be parallel BUT it doesn't always have to have a positive slope for it to be parallel like in question 1.
3. C. never, If they have the same slope they are parallel despite whatever the y-intercept is.
Answer: The incidence of skin cancer (melanoma) has been underestimated.
Step-by-step explanation: The frequency of melanoma is more than 20 times higher in whites than in black Americans. In general, the risk of melanoma in the course of life is approximately 2.6% (1 in 38) for whites, 0.1% (1 in 1.000) for black people and 0.58% (1 in 172) for Hispanics. the risk for each person can be affected by a different number of factors.
Answer:
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Step-by-step explanation:
A parallelogram has opposite parallel sides and it is a quadrilateral.